Youth violence presents a public health challenge of critical importance. There is growing optimism that violence prevention efforts can be effective. The mechanisms, however, whereby treatment and prevention programs exert lasting violence reduction effects are not well understood. In the proposed study, the investigators examine whether an effective treatment encourages desistance by facilitating the kinds of positive life events related to peers, family, workplace, and romantic relationships that have been associated with desistance from violence in populations of serious youthful offenders. The proposed research builds on an ongoing study of drug abuse among serious juvenile offenders and draws on developmental models of criminal behavior to examine the long-term effects of an effective adolescent treatment model on desistance from serious offending and violence. RAND's Adolescent Outcomes Project is an ongoing study of 449 youths referred by Probation to the Phoenix Academy of Los Angeles (PHA; n=175), or to one of six residential group homes (n=274). The sample is representative of youths sent to large residential treatment programs by the Los Angeles Probation Department. Now, as part of a separate NIDA-funded study, survey waves are being conducted 72, 87 and 102 months after the baseline interviews, creating the opportunity to examine transitions to young adulthood when desistance from crime and violence is most likely to occur. The principal aims of the study are to: 1) identify the pathways to desistance from crime and violence as the sample enters young adulthood; 2) identify the psychosocial events during young adulthood that are associated with desistance pathways for this cohort; 3) examine whether any direct effects of treatment on desistance from crime and violence exist; and 4) test if treatment effects on desistance are mediated by treatment effects on key developmental events of young adulthood. This project will be one of the few longitudinal studies of serious youthful offenders to examine desistance during the transition into early adulthood, and the only one to examine the effect of treatment on desistance during this period. [unreadable] [unreadable] [unreadable]